Method for making housing

ABSTRACT

A method of making a housing includes: providing a substrate and cutting the substrate to form an opening. The substrate being spaced by the opening to form at least one main base. A plurality of metal sheets and a plurality of reinforcing members are provided. Placing the metal sheets, the reinforcing members and the main base into a mold. The metal sheets is positioned in the opening, adjusts width of each gap between adjacent metal sheets, and between the main base and one metal sheet adjacent to the main base. Locating the reinforcing members in the metal sheets and the main base. Liquid resin is filled into the gaps and covers the reinforcing members to bond the metal sheets, the main base and the reinforcing members together, forming the housing.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division application of U.S. patent applicationentitled “HOUSING, ELECTRONIC DEVICE USING SAME, AND METHOD FOR MAKINGSAME” with application Ser. No. 14/687,504, filed on Apr. 15, 2015 andhaving the same assignee as the instant application.

This application claims priority to Chinese Patent Application No.201410807706.9 filed on Dec. 23, 2014, and claims priority to U.S.patent application Ser. No. 14/687,504, filed on Apr. 15, 2015, thecontents of which are incorporated by reference herein.

FIELD

The subject matter herein generally relates to a housing, an electronicdevice using the housing, and a method for making the housing.

BACKGROUND

Metal housings are widely used for electronic devices such as mobilephones or personal digital assistants (PDAs). Antennas are alsoimportant components in electronic devices. But the signal of theantenna located in the metal housing is often shielded by the metalhousing.

BRIEF DESCRIPTION OF THE FIGURES

Implementations of the present technology will now be described, by wayof example only, with reference to the attached figures.

FIG. 1 is an isometric view of an electronic device, according to anexemplary embodiment.

FIG. 2 is an isometric view of a housing of the electronic device shownin FIG. 1, according to a first exemplary embodiment.

FIG. 3 is similar to FIG. 2, but shown from another angle.

FIG. 4 is an exploded, isometric view of the housing shown in FIG. 2.

FIG. 5 is similar to FIG. 4, but shown from another angle.

FIG. 6 is an enlarged, isometric view of a circled portion VI shown inFIG. 5.

FIG. 7 is an enlarged, isometric view of a circled portion VII shown inFIG. 5.

FIG. 8 is a cross-sectional view of the housing along line VIII-VIII ofFIG. 2.

FIG. 9 is an isometric view of a housing of the electronic device shownin FIG. 1, according to a second exemplary embodiment.

FIG. 10 is an exploded, isometric view of the housing shown in FIG. 9.

FIG. 11 is a cross-sectional view of the housing along line XI-XI ofFIG. 9.

FIG. 12 is an isometric view of a housing of the electronic device shownin FIG. 1, according to a third exemplary embodiment.

FIG. 13 is a cross-sectional view of the housing along line XII-XII ofFIG. 12.

FIG. 14 is an isometric view of a housing of the electronic device shownin FIG. 1, according to a third exemplary embodiment.

FIG. 15 is a cross-sectional view of the housing along line XV-XV ofFIG. 14.

FIG. 16 is a flow chart of a method for making a housing in accordancewith an exemplary embodiment.

FIG. 17 is a flow chart of a method for making a housing in accordancewith another exemplary embodiment.

DETAILED DESCRIPTION

It will be appreciated that for simplicity and clarity of illustration,where appropriate, reference numerals have been repeated among thedifferent figures to indicate corresponding or analogous elements. Inaddition, numerous specific details are set forth in order to provide athorough understanding of the embodiments described herein. However, itwill be understood by those of ordinary skill in the art that theembodiments described herein can be practiced without these specificdetails. In other instances, methods, procedures and components have notbeen described in detail so as not to obscure the related relevantfeature being described. Also, the description is not to be consideredas limiting the scope of the embodiments described herein. The drawingsare not necessarily to scale and the proportions of certain parts may beexaggerated to better illustrate details and features of the presentdisclosure.

The term “comprising,” when utilized, means “including, but notnecessarily limited to”; it specifically indicates open-ended inclusionor membership in the so-described combination, group, series and thelike. The term “coupled” when utilized, means “either a directelectrical connection between the things that are connected, or anindirect connection through one or more passive or active intermediarydevices, but not necessarily limited to”.

FIG. 1 illustrates an electronic device 100 according to an exemplaryembodiment. The electronic device 100 can be, but not limited to, amobile phone, a personal digital assistant or a tablet computer. Theelectronic device 100 includes a body 10, a housing 30 assembled to thebody 10, and an antenna 50 located inside the housing 30.

FIGS. 2-5 illustrate that the housing can have a sheet shape. In atleast one exemplary embodiment, the housing 30 can be a back cover ofthe electronic device 100. The housing 30 include a substrate 31, aplurality of metal sheets 33, a plurality of connecting members 35, aplurality of reinforcing member 37 located in the substrate 31 and themetal sheets 33, a non-conductive member 39 and a protective layer (notshown) formed on a surface of the substrate 31. The substrate 31 canbond with the metal sheets 33 through the connecting members 35.

The substrate 31 can be made of a metal which can be selected from agroup consisting of stainless steel, aluminum, aluminum alloy,magnesium, magnesium alloy, titanium, titanium alloy, copper and copperalloy.

FIG. 5-6 illustrate that the substrate 31 includes a footwall 311, twoopposite sidewalls 313 and two pairs of two opposite fasteningstructures 315. The sidewalls 313 are respectively located at twoopposite sides of the footwall 311. The two pairs of two oppositefastening structures 315 are respectively located at two opposite sidesof the substrate 31.

In at least one exemplary embodiment, the thickness of the footwall 311and the sidewalls 313 are all less than 0.5 mm; preferably, thethickness of the footwall 311 and the sidewalls 313 can be about 0.3 mmto about 0.5 mm.

The two opposite sides of the footwall 311 both has a plurality ofgrooves 3111 corresponding to the fastening structures 315. In at leastone exemplary embodiment, the number of the grooves 3111 can be eight.The sidewall 313 also has a plurality of grooves 3131 corresponding tothe fastening structures 315. In at least one exemplary embodiment, thenumber of the grooves 3131 can be eight.

In at least one exemplary embodiment, a surface of each sidewall 313forms a accommodating groove 3133, the non-conductive member 39 cancover at least a portion of the footwall 311 and the accommodatinggroove 3133.

In alternative embodiments, a surface of each sidewall 313 does not forman accommodating groove 3133, the non-conductive member 39 can cover atleast a portion of the footwall 311 and the sidewall 313.

It is to be understood that the location, the shape, and the dimensionof the at least a portion can be designed according to the housing 30.

One end of each fastening structure 315 is located at the sidewall 313,the opposite end of the fastening structure 315 is located at thefootwall 311 along a direction extending from the sidewall 313 to thefootwall 311. Each end of the fastening structure 315 located at thesidewall 313 also has two through-holes 3151 corresponding to thegrooves 3131, each end of the fastening structure 315 located at thefootwall 311 has two through-holes 3153 corresponding to the grooves3111. The number of the through-holes 3151, 3153 can both be eight. Thethrough-holes 3151, 3153 can cooperate with the grooves 3131, 3111 toreceive reinforcing members 37.

FIGS. 7-8 illustrates that a portion of the substrate 31 has an opening317 by cutting the substrate 31. The metal sheets 33 and the connectingmember 35 can be positioned in the opening 317. The antenna 50 alignswith the opening 317, the connecting members 35 and the non-conductivemember 39, such that signal can pass through the substrate 31. In atleast one exemplary embodiment, the substrate 31 can be spaced by theopening 317, forming two separated main bases 318.

A dielectric layer (not shown) can be formed on a surface of each mainbody 318. The dielectric layer has a thickness of about 8 μm to about 25μm. In at least one exemplary embodiment, the dielectric layer can beformed through an anodic oxidation process, the dielectric layer has athickness of about 8 μm to about 15 μm, and a plurality of holes (notshown) can be formed on the dielectric layer. In alternativeembodiments, the dielectric layer can be formed by spraying insulativepaint on the main bases 318, the dielectric layer has a thickness ofabout 15 μm to about 25 μm. The insulative paint can be a polyesterpaint, a polyurethane paint or a polyamide-imide paint.

It is to be understood that the main bases 318 cannot couple with theantenna 50 as the main bases 318 are covered with the dielectric layer,such that the main bases 31 are not used as a part of the antenna 50assembly of the electronic device 100, signals of the antenna 50 canpass through the opening 317, such that the antenna 50 can have a highradiation efficience.

A dielectric layer (not shown) can also be formed on each metal sheet33. The dielectric layer has a thickness of about 8 μm to about 25 μm.In at least one exemplary embodiment, the dielectric layer can be formedthrough an anodic oxidation process, the dielectric layer has athickness of about 8 μm to about 15 μm, and a plurality of holes (notshown) can be formed on the dielectric layer. In alternativeembodiments, the dielectric layer can be formed by spraying insulativepaint on the metal sheets 33, the dielectric layer has a thickness ofabout 15 μm to about 25 μm. The insulative paint can be a polyesterpaint, a polyurethane paint or a polyamide-imide paint.

Each metal sheet 33 includes an end wall 331, and two sidewalls 333, thesidewalls 333 are perpendicularly connected with two opposite ends ofthe end wall 331, respectively, as shown in FIGS. 5-6. Each metal sheet33 has a width of about 0.15 mm to about 1.0 mm along a direction from aconnecting member 35 located at one side of a metal sheet 33 to anadjacent connecting member 35 located at the opposite side of the metalsheet 33. The metal sheets 33 can be made of a metal which can beselected from a group consisting of stainless steel, aluminum, aluminumalloy, magnesium, magnesium alloy, titanium, titanium alloy, copper andcopper alloy.

Two opposite ends of the end wall 331 both have a cavity 3311. The endwall 331 has a width of about 0.8 mm to about 1.0 mm perpendicular to adirection from a connecting member 35 located at one side of a metalsheet 33 to an adjacent connecting member 35 located at the oppositeside of the metal sheet 33.

Each sidewall 333 includes a bending member 3331 and an extending member3333.

The two opposite ends of each end wall 331 bend along a directionperpendicular to the end wall 331, forming the bending members 3331.Each bending member 3331 has a cavity 3335. Each bending member 3331 hasa width of about 0.8 mm to about 1.0 mm perpendicular to a directionfrom a connecting member 35 located at one side of a metal sheet 33 toan adjacent connecting member 35 located at the opposite side of themetal sheet 33.

Each bending member 3331 extends away from the end wall 331, forming theextending member 3333. Each extending member 3333 has a width of about0.3 mm to about 0.5 mm perpendicular to a direction from a connectingmember 35 located at one side of a metal sheet 33 to an adjacentconnecting member 35 located at the opposite side of the metal sheet 33.The width of the extending members 333 is equal to the thickness of thesidewall 313.

The metal sheets 33 can be positioned in the opening 317 of thesubstrate 31. Gaps 319 between each two adjacent dielectric layerscovered on the metal sheets 33 have a width of about 0.02 mm to about0.7 mm along a direction from a connecting member 35 located at one sideof a metal sheet 33 to an adjacent connecting member 35 located at theopposite side of the metal sheet 33. Gaps 319 between the dielectriclayers covered on the main bases 318 and the adjacent dielectric layerscovered on the metal sheets 33 adjacent to the main bases 318 have awidth of about 0.02 mm to about 0.7 mm along a direction from aconnecting member 35 located at one side of a metal sheet 33 to anadjacent connecting member 35 located at the opposite side of the metalsheet 33. The connecting members 35 can be respectively positioned inthe gaps 319, and connected with the dielectric layers of the metalsheets 33 and the main bases 318, such that each two adjacent metalsheets 33, and the main bases 318 and the metal sheets 33 adjacent tothe main bases 318 can be bonded together. The connecting member 35 hasa width of about 0.02 mm to about 0.7 mm along a direction from aconnecting member 35 located at one side of a metal sheet 33 to anadjacent connecting member 35 located at the opposite side of the metalsheet 33.

It is to be understood, the metal sheets 33 and the main bases 318 donot have the dielectric layer, and gaps 319 between each two adjacentmetal sheets 33 can be about 0.02 mm to about 0.7 mm along a directionfrom a connecting member 35 located at one side of a metal sheet 33 toan adjacent connecting member 35 located at the opposite side of themetal sheet 33. Gaps 319 between the main bases 318 and the metal sheets33 adjacent to the main bases 318 can be about 0.02 mm to about 0.7 mmalong a direction from a connecting member 35 located at one side of ametal sheet 33 to an adjacent connecting member 35 located at theopposite side of the metal sheet 33. The connecting member 35 can bepositioned in the gaps 319 respectively, and directly connected with themetal sheets 33 and the main bases 318, such that each two adjacentmetal sheets 33, and the main bases 318 and the metal sheets 33 adjacentto the main bases 318 can be bonded together.

It is to be understood that, when the metal sheets 33 and the main bases318 are not covered with the dielectric layers, the substrate 31 can becoupled with the antenna 50, and the substrate 31 can be a part of theantenna 50 assembly of the electronic device 100, signals of the antenna50 can pass through the gaps 319, such that the antenna 50 can have ahigh radiation efficience.

In alternative embodiments, when the metal sheets 33 and the main bases318 are not covered with dielectric layers, the substrate 31 is notcoupled with the antenna 50, such that the main bases 31 is not used asa part of the antenna 50 assembly of the electronic device 100, signalsof the antenna 50 can pass through the gaps 319 and the non-conductivemember 35, such that the antenna 50 can have a high radiationefficience.

The connecting member 35 can be made of one of a resin, a rubber, and aceramic.

The resin can be a thermoplastic or a thermosetting plastic. Thethermoplastic can be selected from a group consisting of polybutyleneterephthalate (PBT), polyphenylene sulfide (PPS), polyethyleneterephthalate (PET), polyether ether ketone (PEEK), polycarbonate (PC),polyvinyl chloride (PVC). The thermosetting plastic can be selected froma group consisting of an epoxy, and a polyurea resin, and a UV-curingadhesive. The UV-curing adhesive can be an acrylic resin or apolyurethane resin.

The reinforcing member 37 can be made of a metal or a glass fiber.

When the reinforcing member 37 is made of metal, a surface of thereinforcing member 37 has rolling patterns through a knurling process.The rolling patterns can enhance bonding strength among the reinforcingmembers 37, the substrate 31, the metal sheets 33 and the connectingmembers 35. Each reinforcing member 37 can have an isolative layer (notshown) through a spraying process or an electrophoresis process. Theisolative layer can have a thickness of about 10 μm to about 30 μm. Theisolative layer covers the reinforcing members 37, and can prevent thesignals of the antenna 50 from being affected by the reinforcing members37. The isolative layer can be made of an epoxy paint or an insulativepaint. The insulative paint can be a polyester paint, a polyurethanepaint or a polyamide-imide paint. The main chain of the epoxy paint canincludes polyether and diol alcohol, polyether and diamine or polyesterand diamine at the main chain of epoxy. The isolative layer has athickness of about 10 μm to about 15 μm when the isolative layer is madeof the epoxy paint, and has a thickness of about 15 μm to about 30 μmwhen the isolative layer is made of the insulative paint.

When the reinforcing member 37 is made of the glass fiber, a surface ofthe reinforcing member 37 can have a protective layer through a coatingprocess, a dipping process or an injection process. The protective layercovers the glass fiber, and can prevent the glass fiber from beingdamaged. The protective layer has a thickness of about 0.02 mm to about0.5 mm. The protective layer can be made of a thermoplastic or athermosetting plastic. The thermoplastic can be selected from a groupconsisting of polybutylene terephthalate (PBT), polyphenylene sulfide(PPS), polyethylene terephthalate (PET), polyether ether ketone (PEEK),polycarbonate (PC), polyvinyl chloride (PVC). The thermosetting plasticcan be selected from a group consisting of an epoxy, and a polyurearesin, and a UV-curing adhesive. The UV-curing adhesive can be anacrylic resin or a polyurethane resin.

One end of the reinforcing member 37 can successively pass through onegroove 3111 formed on the footwall 311, one through-hole 3153 connectedwith the groove 3111, a cavity 3311 adjacent to the through-hole 3153,another through-hole 3153 facing the through-hole 3153, then the end ofthe reinforcing member 37 can be partly bended to form a hook 371.Opposite end of the reinforcing member 37 can also successively passthrough another groove 3111 formed on the footwall 311 adjacent to thegroove 3111, another through-hole 3153 connected with the another groove3111, the cavity 3311 adjacent to the through-hole 3153, a through-hole3153 facing the another through-hole 3153, then the opposite end of thereinforcing member 37 can be partly bended to form another hook 371. Thehooks 371 can prevent the reinforcing member 37 from being escaped fromthe grooves 3111, cavities 3311 and the through-holes 3153.

One end of the reinforcing member 37 can successively pass through onegroove 3131 formed on the sidewall 313, one through-hole 3151 connectedwith the groove 3131, a cavity 3335 adjacent to the through-hole 3151,another through-hole 3151 facing the through-hole 3151, then the end ofthe reinforcing member 37 can be partly bended to form a hook 371.Opposite end of the reinforcing member 37 can also successively passthrough another groove 3131 formed on the sidewall 313, anotherthrough-hole 3151 connected with the another groove 3131, the cavity3335 adjacent to the through-hole 3151, a through-hole 3151 facing theanother through-hole 3151, then the opposite end of the reinforcingmember 37 can be partly bended to form another hook 371. The hooks 371can prevent the reinforcing member 37 from being escaped from the groove3131, cavities 3335 and the through-holes 3151.

The non-conductive member 30 can cover at least a portion of thefootwall 311 and the sidewalls 313. The non-conductive member 30 can beformed on a bottom of the opening 317. The metal sheets 33, the mainbases 318, the reinforcing members 37 and the connecting members 30 allbond with the non-conductive member 39.

The non-conductive member 39 can be made of a thermoplastic or athermosetting plastic. The thermoplastic can be selected from a groupconsisting of polybutylene terephthalate (PBT), polyphenylene sulfide(PPS), polyethylene terephthalate (PET), polyether ether ketone (PEEK),polycarbonate (PC), polyvinyl chloride (PVC). The thermosetting plasticcan be selected from a group consisting of an epoxy, and a polyurearesin, and a UV-curing adhesive. The UV-curing adhesive can be anacrylic resin or a polyurethane resin.

It is to be understood that the non-conductive member 39 can be alsomade of a glass or a ceramic.

The protective layer (not shown) can be formed on the housing 30 througha spraying process, an anodic oxidation process, or an electrophoresisprocess. The protective layer has a thickness of about 10 μm to about 15μm.

FIGS. 9-11 illustrate a housing 40 according to a second exemplaryembodiment. The housing 40 includes a substrate 41, a plurality of metalsheets 43, a plurality of connecting members 45, a plurality ofreinforcing members 47 positioned in the substrate 41 and the metalsheets 43, and a non-conductive member 49. The substrate 41 includes amain base 418, a footwall 411, at least one sidewall 413 having anaccommodating groove 4133, and an opening 317. The connecting members 45are respectively positioned in gaps 419 between each two adjacent metalsheets 43, and between the main base 418 and the metal sheet 43 adjacentto the main base 418, such that the metal sheets 43 and the main base418 can be bonded together.

The difference between the housing 40 of the second exemplary embodimentand the housing 30 of the first exemplary embodiment is that the opening417 can be positioned within the substrate 41, and the opening 417cannot run through at least one end of the metal substrate 41 along adirection of the metal sheets 43 parallel to the main base 418. Thenumber of the main base 418 can be one.

FIGS. 12-13 illustrate a housing 50 according to a third exemplaryembodiment. The housing 50 includes a substrate 51, a plurality of metalsheets 53, a plurality of connecting members 55, a plurality ofreinforcing members (not shown) positioned in the substrate 51 and themetal sheets 53, and a non-conductive member 59. The substrate 51includes two main bases 518, a footwall 511, at least one sidewall 513having an accommodating groove 5133, and an opening 517. The connectingmembers 55 are respectively positioned in gaps 519 between each twoadjacent metal sheets 53, and between the main bases 518 and the metalsheets 53 adjacent to the main bases 518, such that the metal sheets 53and the main bases 518 can be bonded together.

The difference between the housing 50 of the third exemplary embodimentand the housing 30 of the first exemplary embodiment is that a thicknessof the footwall 513 is more than 0.5 mm. Preferably, the thickness ofthe footwall 513 is about 0.8 mm to about 1.0 mm. Sections of a portionof a surface of the footwall 513 can be thinned to form a groove 5113 bya thinning process. The non-conductive member 59 can be received in thegroove 5113. The thickness of the footwall 513 corresponding to thegroove 53113 can be about 0.3 mm to about 0.5 mm. The thinning processcan be carried out by a computer number control technology (CNC). It isto be understood that the non-conductive member 59 can also cover aperiphery of groove 5113 to enhance the bonding strength between thenon-conductive member 59 and the footwall 511.

FIGS. 14-15 illustrate a housing 60 according to a fourth exemplaryembodiment. The housing 60 includes a substrate 61, a plurality of metalsheets 63, a plurality of connecting members 65, a plurality ofreinforcing members (not shown) positioned in the substrate 61 and themetal sheets 63, and a non-conductive member 69. The substrate 61includes a main base 618, a footwall 611, at least one sidewall 613having an accommodating groove 6133, and an opening 617. The connectingmembers 65 are respectively positioned in gaps 619 between each twoadjacent metal sheets 63, and between the main base 618 and the metalsheets 63 adjacent to the main base 618, such that the metal sheets 63and the main bases 618 can be bonded together.

The difference between the housing 60 of the fourth exemplary embodimentand the housing 40 of the second exemplary embodiment is that athickness of the footwall 611 is more than 0.5 mm. Preferably, thethickness of the footwall 611 is about 0.8 mm to about 1.0 mm. Sectionsof a portion of a surface can be thinned to form a groove 6113 by athinning process. Non-conductive member 69 can be received in the groove6113. A thickness of the footwall 611 corresponding to the groove 6113can be about 0.3 mm to about 0.5 mm. The thinning process can be carriedout by a CNC technology. It is to be understood that the non-conductivemember 69 can also cover a periphery of groove 6113 to enhance thebonding strength between the non-conductive member 69 and the footwall611.

Referring to FIG. 16, a flowchart is presented in accordance with anexample embodiment. The method 1600 is provided by way of example, asthere are a variety of ways to carry out the method. The method 1600described below can be carried out using the configurations illustratedin FIGS. 1-8, for example, and various elements of these figures arereferenced in explaining example method 1600. Each block shown in FIG.16 represents one or more processes, methods or subroutines, carried outin the example method 1600. Furthermore, the order of blocks isillustrative only and the order of the blocks can change according tothe present disclosure. Additional blocks can be added or fewer blockscan be utilized, without departing from this disclosure. The examplemethod 1600 for making the housing 30 can begin at block 1601.

At block 1601, a substrate 31 having a desired three-dimensional shapeof the housing 30 is provided. The substrate 31 can be made by casting,punching, or computer number control. The substrate 31 can be made of ametal which can be selected from a group consisting of stainless steel,aluminum, aluminum alloy, magnesium, magnesium alloy, titanium, titaniumalloy, copper and copper alloy.

The substrate 31 includes a footwall 311, two opposite sidewalls 313 andtwo pairs of two opposite fastening structures 315. The sidewalls 313are respectively located at two opposite sides of the footwall 311. Thetwo pairs of two opposite fastening structures 315 are respectivelylocated at two opposite sides of the substrate 31. In at least oneexemplary embodiment, the thickness of the footwall 311 and thesidewalls 313 are all less than 0.5 mm; preferably, the thickness of thefootwall 311 and the sidewalls 313 can be about 0.3 mm to about 0.5 mm.

The two opposite sides of the footwall 311 both has a plurality ofgrooves 3111 corresponding to the fastening structures 315. In at leastone exemplary embodiment, the number of the grooves 3111 can be eight.

In at least one exemplary embodiment, a surface of each sidewall 313forms an accommodating groove 3133, the non-conductive member 39 cancover at least a portion of the footwall 311 and the sidewalls 313, andcan be positioned in the accommodating grooves 3133. Portions of thesidewall 313 corresponding to the accommodating grooves 3133 can have athickness of about 0.2 mm to about 0.4 mm.

It is to be understood that the location, the shape and the dimension ofthe at least a portion can be designed according to the housing 30.

The sidewall 313 also has a plurality of grooves 3131 corresponding tothe fastening structures 315. In at least one exemplary embodiment, thenumber of the grooves 3131 can be eight.

In alternative embodiments, a surface of each sidewall 313 does not forman accommodating groove 3133, the non-conductive member 39 can cover atleast a portion of the footwall 311 and the sidewalls 313.

One end of each fastening structure 315 is located at one sidewall 313,the opposite end of the fastening structure 315 is located at thefootwall 311 along a direction extending from the sidewall 313 to thefootwall 311. Each end of the fastening structures 315 located at thesidewall 313 has two through-holes 3151 connected with groove 3131, andeach end of the fastening structures 315 located at the footwall 311 hastwo through-holes 3153 connected with groove 3111. In at least oneexemplary embodiment, the number of the through-holes 3151, 3153 can beeight. The reinforcing members 37 can be positioned in the grooves 3111,3131 and the through-holes 3151, 3153.

At block 1602, the substrate 31 is cut off, forming an opening 317. Thesubstrate 31 can be spaced by the opening 317 and forms at least onemain base 318. In at least one exemplary embodiment, the substrate 31can be cut off by a computer numerical control process, or a lasercutting technology.

In at least one exemplary embodiment, the substrate 31 can be spaced bythe opening 317 and forms two main bases 318.

At block 1603, a dielectric layer (not shown) is formed on a surface ofeach main base 318 through a surface treatment process. The dielectriclayer has a thickness of about 8 μm to about 25 μm. The surfacetreatment process can be carried out by either of the following twomethods:

In a first method, the surface treatment can be carried out in asulfuric acid solution having a concentration of about 160-220 g/L, withthe main bases 318 being an anode, and a stainless steel board being acathode. The voltage between the anode and the cathode is about 10 V toabout 15 V. The temperature of the sulfuric acid is about 16° C. toabout 18° C. The surface treatment process can last for about 30 minutesto about 45 minutes to form the dielectric layers on the main bases 318.The dielectric layer has a thickness of about 10 μm to about 15 μm. Thedielectric layer has a plurality of pores (not shown).

In a second method, the dielectric layer is formed by sprayinginsulative paint onto the surface of the metal bases 318. The dielectriclayer has a thickness of about 15 μm to about 25 μm. The insulativepaint can be a polyester paint, a polyurethane paint or apolyamide-imide paint.

At block 1604, a plurality of metal sheets 33 having a desiredthree-dimensional shape of the housing 30 is provided. The metal sheets33 can be made by casting, punching, or computer number control. Themetal sheets 33 can be made of a metal which can be selected from agroup consisting of stainless steel, aluminum, aluminum alloy,magnesium, magnesium alloy, titanium, titanium alloy, copper and copperalloy. Each metal sheet 33 has a width of about 0.15 mm to about 1.0 mmalong a direction from a connecting member 35 located at one side of ametal sheet 33 to an adjacent connecting member 35 located at theopposite side of the metal sheet 33.

Each metal sheet 33 includes an end wall 331, and two sidewalls 333, thesidewalls 333 are perpendicularly connected with two opposite ends ofthe end wall 331, respectively.

Two opposite ends of the end wall 331 both have a cavity 3311. The endwall 331 has a width of about 0.8 mm to about 1.0 mm perpendicular to adirection from a connecting member 35 located at one side of a metalsheet 33 to an adjacent connecting member 35 located at the oppositeside of the metal sheet 33.

Each sidewall 333 includes a bending member 3331 and an extending member3333.

The two opposite ends of each end wall 331 bend along a directionperpendicular to the end wall 331, forming the bending members 3331.Each bending member 3331 has a cavity 3335. Each bending member 3331 hasa width of about 0.8 mm to about 1.0 mm perpendicular to a directionfrom a connecting member 35 located at one side of a metal sheet 33 toan adjacent connecting member 35 located at the opposite side of themetal sheet 33.

Each bending member 3331 extends away from the end wall 331, forming theextending member 3333. Each extending member 3333 has a width of about0.3 mm to about 0.5 mm perpendicular to a direction from a connectingmember 35 located at one side of a metal sheet 33 to an adjacentconnecting member 35 located at the opposite side of the metal sheet 33.The width of the extending members 333 is equal to the thickness of thesidewall 313.

At block 1605, a dielectric layer (not shown) is formed on each metalsheet 33 through a surface treatment process. The dielectric layer has athickness of about 8 μm to about 25 μm. The surface treatment processcan be carried out by either of the following two methods:

In a first method, the surface treatment can be carried out in asulfuric acid solution having a concentration of about 160-220 g/L, withthe metal sheets 33 being an anode, and a stainless steel board being acathode. The voltage between the anode and the cathode is about 10 V toabout 15 V. The temperature of the sulfuric acid is about 16° C. toabout 18° C. The surface treatment process can last for about 30 minutesto about 45 minutes to form the dielectric layer on the metal sheets 33.The dielectric layer has a thickness of about 10 μm to about 15 μm. Thedielectric layer has a plurality of pores (not shown).

In a second method, the dielectric layer is formed by sprayinginsulative paint onto the surface of the main sheets 33. The dielectriclayer has a thickness of about 15 μm to about 25 μm. The insulativepaint can be a polyester paint, a polyurethane paint or apolyamide-imide paint.

At block 1606, a plurality of reinforcing members 37 is formed by any ofthe following four methods.

In a first method, a metal wire is provided. Rolling patterns can beformed on a surface of the metal wire through a knurling process. Then,the metal wire can be cut off to form a plurality of reinforcing members37. An isolative layer can be formed on each reinforcing member 37through an electrophoresis process or a spraying process. The isolativelayer has a thickness of about 20 μm to about 30 μm. The reinforcingmembers 37 coated with the isolative layer would not affect signals ofthe antenna 50.

The electrophoresis process can be carried out in an electrophoresissolution having a temperature of about 30-37° C., with the reinforcingmembers 37 being an anode, and a stainless steel board being a cathode.The voltage between the anode and the cathode is about 70 V to about 90V. The surface treatment process can last for about 20 seconds to about44 seconds to form the isolative layers. The isolative layer has athickness of about 10 μm to about 15 μm. The electrophoresis solutionincludes electrophoresis paint and water with a volume ration of about3-5:4-6. The electrophoresis paint can be an epoxy paint, the main chainof the epoxy paint can have polyether and diol alcohol, polyether anddiamine or polyester and diamine.

The isolative layer can be also formed by spraying insulative paint onthe metal wire. The insulative paint can be a polyester paint, apolyurethane paint or a polyamide-imide paint. The isolative layer has athickness of about 15 μm to about 30 μm.

It is to be understood that the metal wire can be replaced by metal rod.

In a second method, a glass fiber is provided. The glass fiber is putinto a mold (not shown). Liquid resin can be filled into the mold andcover the glass fiber, forming the reinforcing member 37 having anisolation layer, the isolative layer can protect the reinforcing member37 from been damaged. The isolative layer has a thickness of about 0.02mm to about 0.5 mm.

In a third method, a glass fiber is provided. The glass fiber can bedipped in a molten resin solution, resin covers the glass fiber, thenthe glass fiber can be put out off the solution, and dried, forming thereinforcing member 37 having a protective layer. The resin can be driedin an oven, at room temperature, or by a UV radiation. The protectivelayer has a thickness of about 0.02 mm to about 0.5 mm.

In a fourth method, a glass fiber is provided. Molten resin can becoated on the glass fiber, and then the molten resin can be dried toform a protective layer on the glass fiber. The resin can be dried in anoven, at room temperature, or by a UV radiation. The protective layerhas a thickness of about 0.02 mm to about 0.5 mm.

The protective layer can be made of a thermoplastic or a thermosettingplastic. The thermoplastic can be selected from a group consisting ofpolybutylene terephthalate (PBT), polyphenylene sulfide (PPS),polyethylene terephthalate (PET), polyether ether ketone (PEEK),polycarbonate (PC), polyvinyl chloride (PVC). The thermosetting plasticcan be selected from a group consisting of an epoxy, and a polyurearesin, and a UV-curing adhesive. The UV-curing adhesive can be anacrylic resin or a polyurethane resin.

The glass fiber can be cut off to form a plurality of reinforcingmembers 37.

At block 1607, a plurality of connecting members 35 and a non-conductivemember are formed through an injection process.

The main bases 318 and the metal sheets 33 can be placed into a mold(not shown), the metal sheets 33 are all sandwiched between the two mainbases 318. Each two adjacent metal sheets 311 having the dielectriclayer, and each main base 318 having the dielectric layer and the metalsheet 311 adjacent to the main base 318 can be spaced by gaps 319.

One end of the reinforcing member 37 can successively pass through onegroove 3111 formed on the footwall 311, one through-hole 3153 connectedwith the groove 3111, a cavity 3311 adjacent to the through-hole 3153,another through-hole 3153 facing the through-hole 3153, and then the endof the reinforcing member 37 can be partly bended to form a hook 371.Opposite end of the reinforcing member 37 can also successively passthrough another groove 3111 formed on the footwall 311 adjacent to thegroove 3111, another through-hole 3153 connected with the another groove3111, the cavity 3311 adjacent to the through-hole 3153, a through-hole3151 facing the another through-hole 3153, and then the opposite end ofthe reinforcing member 37 can be partly bended to form another hook 371.One end of another reinforcing member 37 can successively pass throughone groove 3131 formed on the sidewall 313, one through-hole 3151connected with the groove 3131, a cavity 3335 adjacent to thethrough-hole 3151, another through-hole 3151 facing the through-hole3151, and then the end of the reinforcing member 37 can be partly bendedto form a hook 371. Opposite end of the another reinforcing member 37can also successively pass through another groove 3131 formed on thesidewall 313 adjacent to the groove 3131, another through-hole 3151connected with the groove 3131, the cavity 3335 adjacent to thethrough-hole 3151, a through hole 3151 facing the another through-hole3151, and then the opposite end of the reinforcing member 37 can bepartly bended to form another hook 371. The hooks 371 can prevent thereinforcing members 37 from being escaped from the groove 3131, cavities3331 and the through-holes 3151. The injection temperature can be about290° C. to about 320° C., the injection pressure can be about 2 MPa toabout 4 MPa. Liquid resin can be filled into the gaps 319, the grooves3111, 3131, the through-holes 3151, 3153, cavities 3311, 3335, and coverthe fastening structure 315 and reinforcing members 37. After the resinis cold, the resin can bond the metal sheets 33, the main bases 318 andthe reinforcing members 37 together, the resin received in the gaps 319forms a plurality of connecting members 35. Each gap 319 and eachconnecting member 35 can both have a width of about 0.02 mm to about 0.7mm along a direction from an adjacent non-conductive element 33 locatedat one side of metal sheet 311 to another adjacent non-conductiveelement 33 located at an opposite side of the metal sheet 311. Signalsof the antenna 50 can pass through the connecting members 35, such thatthe antenna 50 has a high radiation efficiency.

The connecting member 35 can be made of a resin, a rubber, or a ceramic.

The resin can be a thermoplastic or a thermosetting plastic. Thethermoplastic can be selected from a group consisting of polybutyleneterephthalate (PBT), polyphenylene sulfide (PPS), polyethyleneterephthalate (PET), polyether ether ketone (PEEK), polycarbonate (PC),polyvinyl chloride (PVC). The thermosetting plastic can be selected froma group consisting of an epoxy, and a polyurea resin, and a UV-curingadhesive. The UV-curing adhesive can be an acrylic resin or apolyurethane resin.

It is to be understood, the metal sheets 33 and the main bases 318 donot form the dielectric layer, and gaps 319 between each two adjacentmetal sheets 33 can be about 0.02 mm to about 0.7 mm along a directionfrom a connecting member 35 located at one side of a metal sheet 33 toan adjacent connecting member 35 located at the opposite side of themetal sheet 33. Gaps 319 between the main bases 318 and the metal sheets33 adjacent to the main bases 318 can be about 0.02 mm to about 0.7 mmalong a direction from a connecting member 35 located at one side of ametal sheet 33 to an adjacent connecting member 35 located at theopposite side of the metal sheet 33. The connecting member 35 can bereceived in the gaps 319 respectively, and directly connected with themetal sheets 33 and the main bases 318, such that each two adjacentmetal sheets 33, and the main bases 318 and the metal sheets 33 adjacentto the main bases 318 can be bonded together.

It is to be understood that, when the metal sheets 33 and the main bases318 do not have the dielectric layer, the substrate 31 can be coupledwith the antenna 50, the substrate 31 can be a part of the antenna 50assembly of the electronic device 100, signals of the antenna 50 canpass through the gaps 319, such that the antenna 50 can have a highradiation efficiency.

In alternative embodiments, when the metal sheets 33 and the main bases318 do not have the dielectric layer, the substrate 31 is not coupledwith the antenna 50, such that the main bases 31 is not used as a partof the antenna 50 assembly of the electronic device 100, signals of theantenna 50 can pass through the gaps 319 and the connecting member 35,such that the antenna 50 can have a high radiation efficience.

During the injection process, liquid resin can cover at least a portionof the footwall 311 and sidewalls 313, and fill the accommodating groove3133. After the resin is cold, the non-conductive members 39 are formed,the non-conductive member 39 can bond with the metal sheets 33, theconnecting members 35, the main bases 318 and the reinforcing members37. The non-conductive member 39 can be formed on a bottom of theopening 317. The non-conductive member 39 can enhance bonding strengthbetween the metal sheets 33 and the main bases 318.

It is to be understood that when the sidewalls 313 do not haveaccommodating groove 3133, the non-conductive member 39 is formed on atleast a portion of the footwall 311 and the sidewalls 313.

The location, the shape, and the dimension of the at least a portion canbe designed according to the housing 30.

The non-conductive member 39 can be made of a thermoplastic or athermosetting plastic. The thermoplastic can be selected from a groupconsisting of polybutylene terephthalate (PBT), polyphenylene sulfide(PPS), polyethylene terephthalate (PET), polyether ether ketone (PEEK),polycarbonate (PC), polyvinyl chloride (PVC). The thermosetting plasticcan be selected from a group consisting of an epoxy, and a polyurearesin, and a UV-curing adhesive. The UV-curing adhesive can be anacrylic resin or a polyurethane resin.

It is to be understood that the non-conductive member 39 can be alsomade of a glass or a ceramic.

At block 1608, a protective layer (not shown) is formed on the substrate31 through a surface treatment process. The surface treatment processcan be carried out by any of the following three methods.

In a first method, the protective layer is formed by an anodic oxidationcoloring process. The anodic oxidation coloring process is carried outin a sulphuric acid solution having a concentration of about 160 g/L toabout 220 g/L, with the substrate 31 being an anode, and a stainlesssteel board being a cathode. The voltage between the anode and thecathode is about 10 V to about 15 V. The temperature of the sulphuricacid is about 16° C. to about 18° C. The anodic oxidation coloringprocess can last for about 30 minutes to about 45 minutes to form theprotective layer having a thickness of about 10 μm to about 15 μm. Theprotective layer has a plurality of pores (not shown). Then, thesubstrate 31 is dipped into a dyeing solution containing coloring agentat a temperature of about 30° C. to about 50° C. The coloring agent hasa concentration of about 3 g/L to about 10 g/L. The dipping time can beabout 1 minute to about 2 minutes. The coloring agent is absorbed intothe pores of the protective layer, such that the protective layer canhave color. The coloring agent is a dark organic coloring agent or adark inorganic coloring agent. The protective layer containing coloringagent should be sealed to fix the coloring agent in the pores. Thesealing treatment can be a boiling water sealing process, a steamsealing process, a nickel acetate sealing process, a potassiumdichromate sealing process, a nickel sulfate sealing process, stearicacid sealing process, or a cold sealing process.

In a second method, the protective layer is formed by an electrophoresisprocess. The electrophoresis process is carried out in anelectrophoresis solution at a temperature of about 30° C. to about 37°C., with the substrate 31 being an anode, and a stainless steel boardbeing a cathode. The voltage between the anode and the cathode is about70 V to about 90 V. The electrophoresis process may last for about 20seconds to about 44 seconds to form the protective layer having athickness of about 10 μm to about 15 μm. The electrophoresis solutionincludes electrophoresis paint and water with a volume ratio of about3-5:4-6. The electrophoresis paint can be an epoxy electrophoresispaint. The main chain of the epoxy electrophoresis paint can havepolyether and dual alcohol, polyether and dual amine, or polyester anddual alcohol.

It is to be understood that the protective layer formed by theelectrophoresis process or the anodic oxidation coloring process cancover an area of the substrate 31. As the width of each connectingmember 35 is very small, it is hard to find out the connecting members35 located in the substrate 31, such that the housing 30 can have anentire metallic appearance.

In a third method, the protective layer is formed by spraying paint ontothe surface of the substrate 31 by a spraying gun (not shown). Then, thesubstrate 31 is put in a dryer to be dried, such that the protectivelayer having a thickness of about 10 μm to about 15 μm is formed on theentail surface of the substrate 31. As the paint can cover the entiresurface of the substrate 31 and the connecting member 35, the substrate31 can have an entire metallic appearance.

A method of making the housing 40 according to a second exemplaryembodiment is difference from the method of making the housing 30according to the first exemplary embodiment. The difference is thatopening 417 can be positioned within the substrate 41, and the opening417 cannot run through at least one end of the metal substrate 41 alonga direction of the metal sheets 43 parallel to the main base 418. Thenumber of the main base 418 can be one.

Referring to FIG. 17, a flowchart is presented according to anotherexemplary embodiment. The method 1700 is provided by way of example, asthere are a variety of ways to carry out the method. The method 1700described below can be carried out using the configurations illustratedin FIGS. 12-13, for example, and various elements of these figures arereferenced in explaining method 1700. Each block shown in FIG. 17represents one or more processes, methods or subroutines, carried out inthe method 1700. Furthermore, the order of blocks is illustrative onlyand the order of the blocks can change according to the presentdisclosure. Additional blocks can be added or fewer blocks can beutilized, without departing from this disclosure. The method 1700 formaking the housing 50 can begin at block 1701.

At block 1701, a substrate 51 having a desired three-dimensional shapeof the housing 50 is provided. The substrate 51 can be made of a metalwhich can be selected from a group consisting of stainless steel,aluminum, aluminum alloy, magnesium, magnesium alloy, titanium, titaniumalloy, copper and copper alloy. In at least one exemplary embodiment, athickness of the substrate 51 is more than 0.5 mm. Preferably, thethickness of the substrate 51 is about 0.8 mm to about 1.0 mm.

The substrate 51 includes a footwall 511, two opposite sidewall 513 andtwo pairs of two opposite fastening structures (not shown). Thesidewalls 513 are respectively located at two opposite sides of thefootwall 511. The two pairs of two opposite fastening structures arerespectively located at two opposite sides of the substrate 51.

In at least one exemplary embodiment, a surface of each sidewall 513forms a groove 5133, the non-conductive member 59 can cover at least aportion of the footwall 511 and the groove 5133.

At block 1702, an accommodation groove 5113 is formed on the footwall311 by a thinning process. Portions of the footwall 511 corresponding tothe groove 5113 can have a thickness of about 0.3 mm to about 0.5 mm.The thinning process can be carried out by a CNC technology.

At block 1703, the substrate 51 is cut off, forming an opening 517. Thesubstrate 51 can be spaced by the opening 517 and forms at least onemain base 518. In at least one exemplary embodiment, the substrate 51can be cut off by a computer numerical control process, or a lasercutting technology.

In at least one exemplary embodiment, the substrate 51 can be spaced bythe opening 517 and forms two main bases 518.

At block 1704, a dielectric layer (not shown) is formed on a surface ofeach main base 518 through a surface treatment process. The dielectriclayer has a thickness of about 8 μm to about 25 μm. The surfacetreatment process is similar with the surface treatment process asillustrated at block 1603.

At block 1705, a plurality of metal sheets 53 having a desiredthree-dimensional shape of the housing 50 is provided. The metal sheets53 can be made by casting, punching, or computer number control. Themetal sheets 53 can be made of a metal which can be selected from agroup consisting of stainless steel, aluminum, aluminum alloy,magnesium, magnesium alloy, titanium, titanium alloy, copper and copperalloy. Each metal sheet 53 has a width of about 0.15 mm to about 1.0 mmalong a direction from a connecting member 55 located at one side of ametal sheet 53 to an adjacent connecting member 55 located at theopposite side of the metal sheet 53.

At block 1706, a dielectric layer (not shown) is formed on a surface ofeach main sheet 53 through a surface treatment process. The dielectriclayer has a thickness of about 8 μm to about 25 μm. The surfacetreatment process is similar with the surface treatment process asillustrated at block 1605.

At block 1707, a plurality of reinforcing members 57 (not shown) isformed. The method of making the reinforcing member 57 of housing 50 issimilar with method of making the reinforcing member of housing 30 asillustrated at block 1606. The reinforcing members can be position inthe substrate 51.

At block 1708, a plurality of connecting members 55 and a non-conductivemember 59 are formed. The method of making the connecting member 55 anda non-conductive member 59 of housing 50 is similar with method ofmaking the connecting member 35 and a non-conductive member 39 ofhousing 30 as illustrated at block 1607.

The connecting member 35 can be positioned in the gaps 519 respectively,and directly connected with the metal sheets 53 and the main bases 518,such that each two adjacent metal sheets 53, and the main bases 518 andthe metal sheets 53 adjacent to the main bases 518 can be bondedtogether.

The non-conductive member 59 can bond with the metal sheets 53, theconnecting members 55, the main bases 518 and the reinforcing members57. The non-conductive member 59 can be formed on a bottom of theopening 517. The non-conductive member 59 can enhance the bondingbetween the metal sheets 53 and the main bases 518.

At block 1709, a protective layer (not shown) is formed on the substrate51 through a surface treatment process, forming the housing 50. Thesurface treatment process is similar with the surface treatment processas illustrated at block 1608.

A method of making the housing 60 according to a fourth exemplaryembodiment is difference from the method of making the housing 50according to the third exemplary embodiment. The difference is thatopening 617 can be positioned within the substrate 61, and the opening617 cannot run through at least one end of the metal substrate 61 alonga direction of the metal sheets 63 parallel to the main base 618. Thenumber of the main base 618 can be one.

It is to be understood, however, that even through numerouscharacteristics and advantages of the present disclosure have been setforth in the foregoing description, together with details of assemblyand function, the disclosure is illustrative only, and changes may bemade in detail, including in the matters of shape, size, and arrangementof parts within the principles of the disclosure to the full extentindicated by the broad general meaning of the terms in which theappended claims are expressed.

What is claimed is:
 1. A method of making a housing comprising:providing a substrate; cutting the substrate to form an opening, thesubstrate being spaced by the opening to form at least one main base; aplurality of metal sheets and a plurality of reinforcing members areprovided; and placing the metal sheets, the reinforcing members and themain base into a mold, the metal sheets being positioned in the opening,adjusting width of each gap between adjacent metal sheets, and betweenthe main base and one metal sheet adjacent to the main base, locatingthe reinforcing members in the metal sheets and the main base, liquidresin being filled into the gaps and covering the reinforcing members tobond the metal sheets, the main base and the reinforcing memberstogether, forming the housing.
 2. The method as claimed in claim 1,wherein the substrate comprises a footwall and two opposite sidewalls,the sidewalls are respectively located at two opposite sides of thefootwall, the method further comprises a step of thinning sections of aportion of the footwall and the sidewalls to form an accommodatinggroove on the footwall and a groove on each sidewall before cutting thesubstrate, a non-conductive member is positioned in the accommodatinggrooves of the footwall and the sidewalls.
 3. The method as claimed inclaim 2, wherein the footwall has a thickness of 0.3 mm to 0.5 mm, eachsidewall has a thickness of 0.2 mm to 0.4 mm.
 4. The method as claimedin claim 2, wherein a surface of each sidewall forms an accommodatinggroove, the non-conductive member covers at least a portion of thefootwall and the sidewalls, and is positioned in the accommodatinggrooves.
 5. The method as claimed in claim 3, further comprising a stepof forming a dielectric layer on the main base and each metal sheet. 6.The method as claimed in claim 5, wherein the dielectric layer has athickness of 8 μm to 25 μm.
 7. The method as claimed in claim 3, furthercomprising a step of forming a plurality of connecting members and anon-conductive member.
 8. The method as claimed in claim 7, wherein eachmetal sheet comprises an end wall and two sidewall, the sidewalls areperpendicularly connected with two opposite ends of the end wallrespectively, two opposite ends of the end wall both have a cavity, theend wall has a width of 0.8 mm to 1.0 mm perpendicular to a directionfrom a connecting member located at one side of a metal sheet to anadjacent connecting member located at the opposite side of the metalsheet.
 9. The method as claimed in claim 7, wherein the connectingmembers are respectively positioned in gaps between each two adjacentmetal sheets, and between each main base and one metal sheet adjacent tothe main base, such that the metal sheets and the main base are bondedtogether through the connecting members.
 10. The method as claimed inclaim 7, wherein each connecting member has a width of 0.02 mm to 0.7 mmalong a direction from an adjacent connecting member located at one sideof metal sheet to another adjacent connecting member located at anopposite side of the metal sheet.
 11. The method as claimed in claim 2,wherein two opposite sides of the footwall both have a plurality ofgrooves, each sidewall also has grooves, the substrate further comprisestwo pairs of two opposite fastening structures, one end of eachfastening structure is located at the sidewall, the opposite end of eachfastening structure is located at the footwall along a directionextending from the sidewall to the footwall, each end of the fasteningstructure located at the sidewall and the footwall has twothrough-holes, the grooves are connected with the correspondingthrough-holes.
 12. The method as claimed in claim 8, wherein eachsidewall of each metal sheet comprises a bending member and an extendingmember, each bending member has a cavity, one end of the reinforcingmember successively passes through one groove formed on the footwall orsidewalls, one through-hole connected with the groove, a cavity adjacentto the through-hole, another through-hole facing the through-hole, andthen the end of the reinforcing member is bended to form a hook,opposite end of the reinforcing member also successively passes throughanother groove formed on the footwall or sidewalls, another through-holeconnected with the groove, the cavity adjacent to the through-hole, athrough-hole facing the another through-hole, and then the opposite endof the reinforcing member is partly bended to form another hook.
 13. Themethod as claimed in claim 12, wherein each bending member have a widthof 0.8 mm to 1.0 mm perpendicular to a direction from a connectingmember located at one side of a metal sheet to an adjacent connectingmember located at the opposite side of the metal sheet, each extendingmember has a width of 0.3 mm to 0.5 mm perpendicular to a direction froma connecting member located at one side of a metal sheet to an adjacentconnecting member located at the opposite side of the metal sheet, thewidth of the extending members is equal to the thickness of thesidewall.
 14. The method as claimed in claim 1, wherein the reinforcingmembers are made of a metal, each reinforcing member has an isolativelayer having a thickness of 10 μm to 30 μm.
 15. The method as claimed inclaim 1, wherein the reinforcing members are made of a glass fiber, eachreinforcing member has a protective layer having a thickness of 0.02 mmto 0.5 mm.